Sancho has been banished from the first team dressing room after he fell out with Manchester United manager Erik ten Hag.
The Dutchman is not ready to reintegrate him as long as the player has not apologised and the winger is not prepared to do so at the moment.
He is now expected to leave Old Trafford in January and Dortmund have been linked with an interest in him.
The winger is open to a return to Dortmund and Terzic has kept the lines of communication open with him.
Dortmund are likely to be more open to signing him if Manchester United are prepared to loan him out.
The Red Devils are believed to be looking for somewhere around €60m before agreeing to sell Sancho.